title: Long term in vivo biotransformation of iron oxide nanoparticles.
abstract: The long term outcome of nanoparticles in the organism is one of the most important concerns raised by the development of nanotechnology and nanomedicine. Little is known on the way taken by cells to process and degrade nanoparticles over time. In this context, iron oxide superparamagnetic nanoparticles benefit from a privileged status, because they show a very good tolerance profile, allowing their clinical use for MRI diagnosis. It is generally assumed that the specialized metabolism which regulates iron in the organism can also handle iron oxide nanoparticles. However the biotransformation of iron oxide nanoparticles is still not elucidated. Here we propose a multiscale approach to study the fate of nanomagnets in the organism. Ferromagnetic resonance and SQUID magnetization measurements are used to quantify iron oxide nanoparticles and follow the evolution of their magnetic properties. A nanoscale structural analysis by electron microscopy complements the magnetic follow-up of nanoparticles injected to mice. We evidence the biotransformation of superparamagnetic maghemite nanoparticles into poorly-magnetic iron species probably stored into ferritin proteins over a period of three months. A putative mechanism is proposed for the biotransformation of iron-oxide nanoparticles.
authors.affiliation: Laboratoire Matières et Systèmes Complexes (MSC), UMR 7057 CNRS/Université Paris-Diderot, 10 Rue Alice Domon et Léonie Duquet, 75205 Paris Cedex 13, France.
authors.forename: Michael
authors.initials: M
authors.lastname: Levy
authors.forename: Nathalie
authors.initials: N
authors.lastname: Luciani
authors.forename: Damien
authors.initials: D
authors.lastname: Alloyeau
authors.forename: Dan
authors.initials: D
authors.lastname: Elgrabli
authors.forename: Vanessa
authors.initials: V
authors.lastname: Deveaux
authors.forename: Christine
authors.initials: C
authors.lastname: Pechoux
authors.forename: Sophie
authors.initials: S
authors.lastname: Chat
authors.forename: Guillaume
authors.initials: G
authors.lastname: Wang
authors.forename: Nidhi
authors.initials: N
authors.lastname: Vats
authors.forename: François
authors.initials: F
authors.lastname: Gendron
authors.forename: Cécile
authors.initials: C
authors.lastname: Factor
authors.forename: Sophie
authors.initials: S
authors.lastname: Lotersztajn
authors.forename: Alain
authors.initials: A
authors.lastname: Luciani
authors.forename: Claire
authors.initials: C
authors.lastname: Wilhelm
authors.forename: Florence
authors.initials: F
authors.lastname: Gazeau
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy; D005290:Ferric Compounds / Q000737:chemistry* / Q000378:metabolism*; D008297:Male; D051379:Mice; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D005290:Ferric Compounds; C000499:ferric oxide